i had a similar happening but not on purpose. when i was six i had a urinary tract infection and kidney reflux stage 4 on both sides. they had to do surgery to fix it. now 12 years later i had to do one more "check-up" with a urologist. i had to get a catheter. once they completely drained me of piss they put some slightly radioactive substance through the opposite way so it showed up on the ultrasounds. since i was drained air went up the cath. then they told me to piss everything out so they could "check my flow" (exact wording). started with dickfarts...